Electrolytic shaping apparatus



2 Sheets-Sheet 1 ATTORNEYS J. J. FALLS Get. 3, 1967 ELECTROLYTIC SHAPING APPARATUS Filed Sept. 5, 1963 R C 0 mmm mm MT T VL NA OLN 4 1 mw z A C m fl J. a o m 0 W J 664 0 2 8 E 3 3K 2 4 2 0 w 2 2 2 2 4 0 e a A 4 4 L.) 2 g f 8 w 3 m 8 r 6 A K ,r i! 3/ M Mum .v, vH www HWWMMWMMWWWWWWWWWW T l. HHU i l I I I l I i i I I l l l i I l I I I ON m M 4 f w C k 3 1 w A M 0 m ,.7 1 6 r 8 4 6 7 m 7 4 &w F a 2 V1 7 6 7 Oct. 3, 1967 FALLS 3,345,281

ELECTROLYTIC SHAPING APPARATUS Filed Sept. 5, 1963 2 Sheets-Sheet 2 F lG-Z F lG-3 82 INVENTOR. JOHN J. ,FALLS v ATTORNEYS United States Patent 3,345,281 ELECTROLYTIC SHAPKNG APPARATUS John J. Falls, Cincinnati, Ohio, assignor to Setco Industries, Inc., Cincinnati, Ohio, a corporation of Ohio Filed Sept. 3, 1963, Ser. No. 306,124 13 Claims. (Cl. 204-212) The present invention relates to an electrolytic shaping apparatus. The electrolytic shaping technique involves charging a current conductive workpiece with a positive electrical charge of high amperage direct current, while rapidly rotating a negatively charged wheel or disc in close proximity to the workpiece in the presence of an electrolytic fluid. By this means, material is removed from the workpiece with great rapidity by electrochemical action rather than by the snagging action common to the use of an abrasive wheel as generally applied.

In practicing the process, the removal of material from the workpiece may be-substantially expedited, by providing means to ensure a steady and copious flow of electrolytic fluid to the space between the workpiece and the working face of the wheel or disc. The wheel or disc employed need not be a grinding wheel or grinding disc with an abrasive surface, but may be simply a plain wheel or disc whose working surface is conductive of low-voltage high-amperage electric current, rotated in slightly spaced relation to the workpiece with a copious supply of electrolytic fluid maintained therebetween.

The process has been satisfactorily performed with the use of wheels or discs fabricated from iron, steel, and various alloys conductive of the electric current employed. Nonferrous metals likewise may be used in fabricating the shaping wheels or discs. Also, wheels or discs of non-conductive materials faced with a conductive material capable of passing current, will satisfactorily perform the electrolytic shaping operation.

One object of the present invention is to provide simple and reliable means for insuring a steady and copious supply of electrolytic fluid to the area between the workpiece and the working face of the shaping wheel or disc, in the performance of an electrolytic shaping or machining operation.

Another object of the invention is to expedite and facilitate the performance of electrolytic shaping operations in any plane of workpiece disposition.

'A further object of the invention is to extend the useful life of shaping wheel or disc, as well as other parts of the apparatus, thereby minimizing servicing and shut-down time with the resultant advantages of gaining greater efficiency and savings of time and labor in performance of the process.

The foregoing and other objects are attained by the means described herein and illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevational view, partly in cross-section, illustrating the improved electrolytic shaping apparatus of the invention. 7

FIG. 2 is an enlarged cross-section of the lower portion of the apparatus shown in FIG. 1.

FIG. 3 is a cross-sectional view taken on line 33 of FIG. 2.

FIG. 4 is an enlarged cross-section taken on line 4-4 of FIG. 2.

The present invention concerns electrolytic shaping apparatus of the general character disclosed in US. Patent No. 2,946,731, dated July 26, 1960, to which the reader may refer for basic information concerning the process involved. The apparatus about to be disclosed herein enhances the performance of the process, and in addition,

provides for most elfective removal of material from a workpiece secured in any position, whether the shaping 3,345,281 Patented Oct. 3, 1967 is performed in a vertical, horizontal, or intermediate angled plane.

Referring to FIG. 1, W indicates a metallic workpiece having a surface 10 to be reduced or finished by removal of material, and 12 indicates a support or bed upon which the workpiece is secured during treatment. The workpiece is connected electrically to a suitable high-amperage lowvoltage direct current source, such as the automatic voltage control device 14 which includes a conductor 16 imposing a positive charge upon the workpiece. If the support or bed 12 is of metal, as it usually is, conductor 16 may be connected thereto rather than to the workpiece directly.

While as here disclosed the workpiece is supported horizontally, it must be understood that its surface 10 could be disposed in any upright or inclined plane without adversely affecting performance of the material-removing procedure, as will be further explained herein.

The numeral 18 denotes a spindle rotationally mounted in anti-friction bearings 20 within a stationary housing 22 supported for adjustment toward and from the workpiece. An insulating sleeve 24 may surround the spindle housing as shown, for safety purposes. The spindle may be rotated in any suitable manner, as by means of a pulley 26 fixed to the upper or tail end of the spindle and beltdriven by an electric motor or equivalent prime mover, not shown. A head plate 28 on the spindle housing may support a commutator or brush casing 30, wherein suitable electrical connection is made with conductor 32 to impose a direct current negative charge to hollow metallic tube 34 which extends longitudinally of spindle 18 within the axial bore 36 thereof.

The interior of tube 34, which carries the negative electric charge, may serve also as a supply pipe for liquid electrolyte. Liquid electrolyte may be introduced into tube 34 at its upper end 38 by way of a rotary union or fitting 40 which receives the liquid from a feed pipe 42 connected to a reservoir or other source of supply. The fitting 40 may be fixedly mounted on the stationary case 30, in a manner to supply liquid electrolyte to the bore 44 of the tube 34 as said tube rotates with spindle 18. The electrolyte leaves the tube at its lower end 46 and is directed to the workpiece as will be explained.

The character 48 indicates a wheel or disc having a rim 50 which is ring-shaped and has its working face 51 in substantial spaced parallelism with workpiece surface 10. Wheel 48 is commonly known as a cup wheel. The wheel includes a planar body portion 52 which is parallel to the working face, and has a central bore 54 in which is snugly received the lower or discharge end 46 of tube 34. Screws 56 or similar fasteners pass through the body of wheel 48 and anchor the wheel to the lower end face 58 at the working end of spindle 18.

Preferably, though not necessarily, a fluid cup 60 may be interposed between the spindle end and wheel 48 to direct electrolyte to the wheel. Cup 60 has an upstanding rim 62 providing an annular channel 64 with an open top, and into. which may be fed liquid electrolyte from a nozzle 66. The cup bottom hasone or more appertures 68 that register with corresponding outwardly directed apertures 70 of the grinding wheel, whereby electrolyte will be centrifuged toward the working face of wheel 48. Tube 76 may be provided with a liquid discharge port in the form of an annular slit 78 which J u) may be either continuous or interrupted throughout its length. The discharge port 78 of course may take various forms, an exampleof which would be a series of holes or nozzles directed toward the perimeter of the grinding wheel face. The numeral 80 denotes a supply pipe for feeding electrolyte to tube 76. Skirt 72 may provide a support for nozzle 56, as shown.

In FIG. 2, the skirt 72 and electrolyte feeders 66 and 76 may have been omitted, but the structure otherwise is similar to FIG. 1 with emphasis upon the feed for electrolyte by way of spindle tube 34. Tube 34 at its lower end is adapted to support an electrolyte flinger which may in the form of a flat disc or wheel 82 secured to the tube at its hub 84 so as to rotate with the tube and the spindle. Liquid electrolyte from the bore of tube 34 is directed to and emerges from a series of ports 86 in hub 84. and is flung by centrifugal force across the upper sloping face 88 of the flinger disc as the disc rotates. The lower face 90 of disc 82 preferably is substantially fiat, and lies in a plane parallel to but offset from the plane of the Working face 51 of wheel 48. That is, the lower face 90 of the flinger will be at all times spaced from the workpiece a distance slightly greater than any space between the workpiece and the working face 51 of the shaping wheel.

It should here be noted that the outer peripheral edge 92. of flinger 82 is chambered downwardly and outwardly to meet the lower face 90 at an angle approximating 30 degrees, and that a corresponding angle is provided for the inner annular wall face 94- of the shaping wheel, including the adjacent inner area 9-6 of the rim section of the wheel. The angling of these areas has been found highly effective to obtain a copious, steady and forceful flow of liquid electrolyte between the working face 51 and the workpiece, as the wheel rotates in slightly spaced relationship to the workpiece. The thickness of the flinger at the outer edge 92 may be about one-sixteenth inch less than the thickness at hub 84.

The method of mounting flinger 82 for receiving electrolyte from feed tube 34 is subject to modification, although in the example illustrated, the flinger is applied directly to the end of the tube by means of a screwthreaded connection 98. In forming this connection, the inner wall of tube 34 may be internally threaded, while the hub 84 of the flinger is externally threaded correspondingly to enter the threaded end of the tube. In the embodiment illustrated, hub 84 is provided with an axial bore 99 which communicates with the bores 86 and with the feed bore 44 of tube 34, thereby to conduct electrolyte from tube 34 to the upper face of flinger 82.

It will readily be appreciated that flinger 82 will effectively distribute electrolyte to the workpiece at any inclination of spindle 18 that is, it will perform as well on a horizontal spindle machine as on an upright spindle machine. This constitutes a decided advantage over the electrolyte feeds shown at 66 and 76 of FIG. 1, which are effective only in connection with upright spindle machines. In practice, feeds 66 and 76 ordinarily are not used when feed of electrolyte is performed by way of the spindle tube 34. In that event, the alternative feed means 66 and 76 may be omitted as in FIG. 2.

The operation of the apparatus is as follows. With the shaping wheel 48 attached to the spindle as previously explained, the spindle is adjusted toward the workpiece until the working face of the wheel is very close to the surface of the workpiece to be finished. Electrolytic fluid is flooded onto the intervening area while a positive electrical charge is imposed on the workpiece, and a negative charge is imposed on the shaping wheel through tube 34. As the wheel rotates in close proximity to the workpiece, metal is removed therefrom principally by electro-chemical action resulting from passage of current in the presence of electrolyte.

The machining of the workpiece is materially expedited, and a high quality finish is obtained, due to the forceful ifeeding of electrolyte continuously and in generous amounts by the means of the present invention. The electrolyte passing the area undergoing machining may be collected and recirculated throughout the machining process.

It is to be understood that various modifications and changes may be made in the structural details of the apparatus, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed is:

11. In an electrolytic shaper, an electrolyte flinger comprising a substantially flat disc having a central portion, and including an upper surface, a lower surface, and a circumferential edge of truncated cone configuration, the edge making an acute angle to the lower surface approximating 30, said upper surface inclined downwardly and outwardly from a maximum thickness adjacent to the central portion of the disc to a minimum thickness at the circumferential edge, an axially bored hub upstanding upon the upper surface of the disc at the central portion thereof, said hub having formed therein radially disposed outlets to direct fluid from the hub bore outwardly over the sloping upper surface of the disc, and means for securing the hub to a rotary driver.

2. A head for an electrolytic shaper, comprising in combination, a rotary cup wheel having a central portion, and a rim including a ring-shaped planar working face, an outer wall bounding said rim, and an inner wall defining a lower cup recess spaced equidistant from the outer limit of the rim, said inner wall being inclined relative to the working face at an angle approximating degrees, an electrolyte flinger comprising a substantially flat disc disposed within the cup recess of the wheel in substantial parallelism with the planar working face of the wheel, said disc having a central portion, an upper surface, a lower surface, and a circumferential edge of truncated cone configuration spaced from the inner wall of the cup wheel rim, said edge meeting the lower surface of the disc at an angle approximating 30 degrees, the upper surface of the disc being inclined downwardly and outwardly from a maximum thickness adjacent to the central portion of the disc to a minimum thickness at the circumferential edge, an axially bored hub upstanding upon the upper surface of the disc at the central portion thereof, said hub having formed therein radially disposed outlets to direct a liquid electrolyte from the hub bore outwardly over the sloping upper surface of the disc and toward the inclined areas of the disc and the cup wheel rim, and means to support the flinger disc and the cup wheel for rotation.

3. A head for an electrolytic shaper, comprising in combination, a rotary cup wheel having a central portion, and a rim including a ring-shaped planar working face, an outer wall bounding said rim, and an inner wall defining a lower cup recess spaced equidistant from the outer limit of the rim, a rotational electrolyte flinger comprising a substantially flat disc disposed within the recess of the cup wheel in substantial parallelism with the planar working face of the wheel, said disc having a central portion, an upper unobstructed surface, a lower surface, and a circumferential edge, said edge being spaced from the inner wall of the cup wheel rim, and means for directing liquid electrolyte over the upper unobstructed surface of the flinger disc, for distribution of the electrolyte toward the working face of the cup wheel by centrifugal force resulting from rotation of the flinger disc, wherein said means for directing liquid electrolyte includes an axially bored hub for conveying electrolyte, upstanding upon the upper surface of the flinger disc at the central portion thereof, and having formed therein lateral outlets to direct the electrolyte outwardly over the upper surface of the disc.

4. An electrolytic apparatus for shaping an electrically charged workpiece, comprising in combination, a housing including bearing means, a longitudinally bored driving spindle rotatably supported by the bearing means, said spindle having a working end and a tail end, a shaping Wheel fixed to the working end of the spindle for rotation therewith, said wheel having a working face operative upon the charged workpiece, means for electrically charging the shaping wheel with a current polarity opposite to that of the workpiece, means for directing electrolytic fluid to the workpiece through the longitudinal bore of the spindle, and means at that end of the bore which is adjacent to the working end of the spindle, for centrifuging electrolytic fluid from the bore outwardly toward the working face of the shaping wheel as the spindle rotates, wherein said last mentioned means comprised a disc rotatable with the spindle and having a peripheral edge in close proximity to the working face of the shaping wheel.

5. A disc as called for in claim 4 comprising a substantially flat plate having a central portion, and including an upper surface, a lower surface, and a circumferential edge bounding said surface, said upper surface inclined downwardly and outwardly from a maximum thickness adjacent the central portion of the plate to a minimum thickness at the bounding edge, and means on and centrally of said upper surface for securing the disc for rotation.

6. A disc as set forth in claim 5, wherein the circumferential edge provides an edge face inclined at an obtuse angle to the upper surface and at an acute angle to the lower surface.

7. A disc as set forth in claim 5, wherein the circumferential edge provides an edge face inclined relative to the lower surface at an acute angle approximating 30, the angle of inclination being obtuse to the upper surface aforesaid.

8. An electrolytic apparatus for shaping an electrically charged workpiece, comprising in combination, a housing, a longitudinally bored driving spindle journaled upon the housing for rotation, said spindle having a working end and a tail end, a shaping wheel fixed to the Working end of the spindle for rotation therewith, said wheel having a circumferential working face operative upon the charged workpiece, means for electrically charging the shaping wheel with a current polarity opposite to that of the workpiece, a depending skirt on the housing including an annular apertured manifold substantially surrounding the shaping wheel in substantially the plane of rotation of said wheel, and means for supplying electrolytic fluid to the manifold, the aperture thereof being disposed for directing said fluid toward the periphery of the shaping wheel, the bore of the driving spindle having an opening adjacent to the shaping wheel for directing electrolytic fluid from said =bore outwardly toward the shaping wheel periphery.

9. An electrolytic apparatus for shaping an electrically charged workpiece, comprising in combination, a housing, a longitudinally bored driving spindle journaled upon the housing for rotation, said spindle having a working end and a tail end, a shaping wheel fixed to the working end of the spindle for rotation therewith, said Wheel having a circumferential working face operative upon the charged workpiece, means for electrically charging the shaping wheel with a current polarity opposite to that of the workpiece, a depending skirt on the housing including an annular manifold having electrolytic fluid delivery means, said manifold substantially surrounding the shaping wheel in substantially the plane of rotation of said wheel, with the fluid delivery means disposed for directing fluid inwardly toward the periphery of the shaping wheel, the bore of the driving spindle adapted to convey electrolytic fluid from the tail end of the spindle to the working end thereof for delivery of fluid from the spindle bore, for centrifuging the fluid from said bore outwardly toward the shaping wheel periphery, said last mentioned means comprising a disc rotatable 'with the spindle, said disc including a peripheral edge disposed closely adjacent to and concentric with the circumferential working face of the shaping wheel, and substantially in the plane of said working face.

10. Apparatus for electrolytically shaping an electrically charged workpiece, comprising in combination, a housing, a longitudinally bored spindle journaled upon the housing for rotation, said spindle having a working end and a tail end at which ends the bore is exposed, the bore being conductive of fluid introduced near the tail end of the spindle, a shaping wheel fixed to the working end of the spindle in position to intercept fluid discharging from the spindle bore at the working end of the spindle, means for ele-ctrically charging the shaping Wheel with a current polarity opposite to that of the workpiece, an annular working face on the shaping wheel subject to wetting by said fluid, a fluid centrifuging disc in the path of discharge of fluid from the spindle bore, and means for rotating said disc, the disc including a peripheral edge disposed closely adjacent to and concentric with the annular working face of the shaping wheel, and disposed substantially in the plane of said working face.

11. An electrolytic apparatus for shaping an electrically charged workpiece, comprising in combination, a housing, a longitudinally bored driving spindle journaled upon the housing for rotation, a shaping wheel of inverted cup shape having a body, a circumferential side wall, and a lower cavity encircled by the side wall, the side wall including an annular planar Working face operative upon the charged workpiece, means securing the shaping wheel upon the working end of the spindle for rotation therewith, the working face of the wheel being exposed to the 'workpiece, an open-ended electric current conductive tube within the spindle bore extending substantially from the tail end of the spindle to the working end thereof, means electrically connecting to the shaping wheel that end of the tube which is open at the working end of the spindle, means near the opposite end of the tube for imposing upon the tube an electrical charge opposite in polarity to the charge upon the workpiece, the tube being receptive of electrolytic fluid at said opposite end thereof for delivery by that open end of the tube which is adjacent to the shaping Wheel, a centrifuging disc disposed within the cavity of the shaping wheel in parallelism therewith, said disc having a peripheral edge in close proximity to the side wall of the cavity, and having a face onto which may flow electrolytic fluid delivered by the spindle tube, and means for rotating the disc to centrifuge fluid toward the working face of the shaping wheel.

12. Apparatus as set forth in claim 11, wherein the peripheral edge of the disc, and the inside face of the wheel cavity wall, are inclined outwardly at an acute angle to the axis of rotation of the spindle.

13. Apparatus as set forth in claim 11, wherein the inside face of the shaping wheel cavity wall is inclined outwardly at an acute angle to the axis of rotation of the spindle.

References Cited UNITED STATES PATENTS 1,539,742 5/ 1925 Joseph 51-267 2,413,016 12/1946 Wiken et al. 51-267 2,626,493 1/ 1953 Speicher 51-267 2,733,562 2/ 1956 Drumrnond 51-267 2,823,496 2/ 1958 Winter 51-267 2,826,019 3/1958 Garrison 51-267 2,840,960 7/ 1958 Booth 51-267 2,848,410 8/ 8 Knuth-Winterfeldt et a1. 204-224 2,946,731 7/1960 Falls 204-224 3,108,941 10/ 1963 Landeck 204-143 3,238,114 3/1963 Halverstadt et a1. 204-224 FOREIGN PATENTS 707,628 6/ 1941 Germany. 748,485 5/1956 Great Britain.

JOHN H. MACK, Primary Examiner. W. VAN SISE, Assistant Examiner. 

4. AN ELECTROLYTIC APPARATUS FOR SHAPING AN ELECTRICALLY CHARGED WORKPIECE, COMPRISING IN COMBINATIN, A HOUSING INCLUDING BEARING MEANS, A LONGITUDINALLY BORED DRIVING SPINDLE ROTATABLY SUPPORTED BY THE BEARING MEANS, SAID SPINDLE HAVING A WORKING END AND A TAIL END, A SHAPING WHEEL FIXED TO THE WORKING END OF THE SPINDLE FOR ROTATION THEREWITH, SAID WHEEL HAVING A WORKING FACE OPERATIVE UPON THE CHARGED WORKPIECE, MEANS FOR ELECTRICALLY CHARGING THE SHAPING WHEEL WITH A CURRENT POLARITY OPPOSITE TO THAT OF THE WORKPIECE, MEANS FOR DIRECTING ELECTROLYTIC FLUID TO THE WORKPIECE THROUGH THE LONGITUDINAL BORE OF THE SPINDLE, AND MEANS AT THAT END OF THE BORE WHICH IS ADJACENT TO THE WORKING END OF THE SPINDLE, FOR CENTRIFUGING ELECTROLYTIC FLUID FROM THE BORE OUTWARDLY TOWARD THE WORKING FACE OF THE SHAPING WHEEL AS THE SPINDLE ROTATES, WHEREIN SAID LAST MENTIONED MEANS COMPRISED A DISC ROTATABLE WIHT THE SPINDLE AND HAVING A PERIPHERAL EDGE IN CLOSE PROXIMITY TO THE WORKING FACE OF THE SHAPING WHEEL. 